#include <iostream>
using namespace std;
int main()
{
	int m,t,s;
	cin >> m >> t >> s;
	int ret;
	if(t == 0)
	{
		cout << "0" << endl;
		return 0;
	}
	if(s%t == 0)
	{
		ret = (m-s/t) > 0 ? (m-s/t): 0;
	}
	else
	{
		ret = (m-s/t-1) > 0 ? (m-s/t-1) : 0;
	}
	cout << ret;
}

